Reaction by which benzaldehyde cannot be prepared

The order of stability of the following tautomeric compounds is \(\mathop {\begin{array}{*{20}{c}}
  {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||} \\ 
  {C{H_2} = C - C{H_2} - C - C{H_3}} 
\end{array}}\limits_{(I)}  \rightleftharpoons \) \(\mathop {\begin{array}{*{20}{c}}
  {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||} \\ 
  {C{H_3} - C - C{H_2} - C - C{H_3}} 
\end{array}}\limits_{(II)}  \rightleftharpoons \) \(\mathop {\begin{array}{*{20}{c}}
  {OH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||} \\ 
  {C{H_3} - C = CH - C - C{H_3}} 
\end{array}}\limits_{(III)} \)

Which of the following pairs of ions is isoelectronic and isostructural ?

Which among the following is a paramagnetic complex? \((\)At. No. \(Mo = 42, Pt = 78)\)

A first order reaction has a rate constant of \(2.303 \times 10^{-3} \;\mathrm{s}^{-1} .\) The time required for \(40 \mathrm{g}\) of this reactant to reduce to \(10\; \mathrm{g}\) will be.....\(s\) [Given that \(\left.\log _{10} 2=0.3010\right]\)

If \(8 \;g\) of a non-electrolyte solute is dissolved in \(114 \;g\) of n-octane to reduce its vapour pressure to \(80 \%,\) the molar mass (in \(g mol ^{-1}\) ) of the solute is Given that molar mass of n-octane is \(114 \;g\; mol ^{-1}\)

Of the following \(0.10\, m\) aqueous solutions, which one will exhibit the largest freezing point depression ?

True nucleus is absent in

Cardiac activities of the heart are regulated by:
A. Nodal tissue
B. A special neural centre in the medulla oblongata
C. Adrenal medullary hormones
D. Adrenal cortical hormones

Choose the correct answer from the options given below :

The percentage of pyridine \((C_5H_5N)\) that forms pyridinium ion \((C_5H_5N^+H)\) in a \(0.10\, M\) aqueous pyridine solution (\(K_b\) for \(C_5H_5N = 1.7 \times 10^{-9}\)) is

Which of the following events does not occur in rough endoplasmic reticulum?

From the following pairs of ions which one is not an iso-electronic pair?

Match Column \(- I\) with Column \(- II.\)

Column \(- I\)	Column \(- II\)
(a) Saprophyte	(i) Symbiotic association of fungi with plant roots
(b) Parasite	(ii) Decomposition of dead organic materials
(c) Lichens	(iii) Living on living plants or animals
(d) Mycorrhiza	(iv) Symbiotic association of algae and fungi

Choose the correct answer from the options given below \((a)\quad (b)\quad  (c)\quad  (d)\)